The use of conical reflectors in the transmission or reception of acoustic energy is old and well known. Conical reflectors have obvious manufacturing advantages over other types of reflectors such as for example elliptically-shaped or parabolic reflectors. Moreover, various types of transducers or acoustic generators have been used in combination with conical reflectors to transmit and/or receive acoustical energy. Usually, the transducers used with conical reflectors have been of cylindrical configuration. Illustrative of these devices are U.S. Pat. Nos. 2,005,741 and 3,243,768.
It is an object of the present invention to provide a transducer for use with conical reflectors that has greater flexibility as respects shading and focusing than conventional cylindrical transducers. It is a further object of the invention to provide a transducer which is simpler to fabricate than conventional cylindrical transducers, and provides a greater flexibility in combination with conical reflectors than a cylindrical transducer.